Lamp socket apparatus



Oct. 25, 1955 c. E. GILBERT 2,721,985

LAMP SOCKET APPARATUS Filed March 30, 1950 3 Sheets-Sheet 1 INVENTOR.

CHARLES E. GILBERT ATTORNEYS Oct. 25, 1955 c. E. GILBERT 2,721,985

LAMP SOCKET APPARATUS Filed March 30, 1950 3 SheetsSheet 2 5J5. czl. 2..

INVENTOR. CHARLES E. GILBERT D n/4 Z ATTORNEYS Oct. 25, 1955 c. E.GILBERT LAMP SOCKET APPARATUS 3 Sheets-Sheet 3 Filed March 50, 1950 pWE. f 1 3 W/ L M m 2 c m w A..- i J E W m m i v l. 9 5 a a y M y j ./L Im em 1 M 1 3 2 9 ATTORNEYS Unite States Patent OflEice LAMP SOCKETAPPARATUS Charles E. Gilbert, New York, N. Margaret Doris Gilbert,Norman Coates, and The Chase National Bank of the City of New York,executors of said Charles E.

Gilbert, deceased Application March 30', 1950, Serial N 152,934 2Claims. Cl. 339 -180) The present invention relates to lamp sockets andtheir associated equipment and is particularly concerned with lampsockets adapted to be fastened to a hickey or similar device such as incandelabra types of lamp sockets and to lamp sockets adapted to beassociated with prongs rigidly secured thereto to serve as plug-inlights or nightlights.

Qne of the objects of the invention is to provide lamp sockets of thesetypes which are simple to fabricate and to assemble with a minimumnumber of parts and assembly steps.

A further object is to provide lamp sockets of these types havingcontact members which may be quickly and easily secured in place inpermanent manner as a step in connecting to conductor cords wheredesired.

It is still another object of the present invention to provide lampsockets in which the bulb may be securely held in place so as not toloosen as a consequence of vibration or the like.

Various other objects and advantages of the invention will appear morefully from the following detailed description of illustrativeembodiments thereof, taken in conjunction with the appended drawings, inwhich,

Figure l is an elevational cross-sectional view of a candelabra typelamp socket and its mounting hickey;

Figure 2 is an elevational cross-sectional view of the device of Figure1 taken along line 22 thereof;

Figure 3 is a top view of the lamp socket shell of the precedingfigures;

Figure 4 is a bottom view of said shell;

Figure 5 is a side elevational view of said shell;

Figure 6 is a further side elevational view taken perpendicularly of theview of Figure 5; I

Figure 7 is a perspective view of a hickey adapted for ready assemblywith the shell of Figures 1 to 6;

Figure 8 is a developed view of one of the contact members adapted to beassembled with the shell of Figures 1 to 6;

Figure 9 is a similarly developed view of another contact member;

Figures 10 and 11 are respective perspective views of modified forms ofthe hickey of Figure 7;

Figure 12 is an elevational cross-sectional view of a lamp socketaccording to the present invention having contact members integrallyformed as plug prongs for insertion into a plug receptacle; 7

Figure 13 is another elevational cross-sectional view along line 1313 ofFigure 12;

Figure 14 is a top view of the lamp socket shell of Figure 12;

Figure 15 is a bottom view of said shell;

Figure 16 is one side view of said shell;

Figure 17 is another side view of said shell viewed perpendicularly toFigure 16;

Figures 18 and 19 are respective developed views of the two contact andprong members of Figures 12 and 13.

Referring to Figures 1 to,9,' there is shown both in 2. assembly anddetail a form of lamp socket adapted for use in candelabra typemountings in which", as is well known, the lamp socket proper is mountedon the end of a conduit by means of a hickey which spaces the socketfrom the end of conduit, a tubular masking member (such as of cardboard,plastic or the like) being slipped around the lamp socket to conceal itand the hickey and to simulate the appearance of a candle, the

bulb when placed in the socket then appearing as the lighted up of sucha simulated candle.

In Figures 1 and 2' such a system is shown comprising a conduit 21 towhose end 25 is affiXed a hickey 22 carrying the lamp socket shell 23which has mounted therein the contact members 24 and 26', the assemblyof shell 23, hickey 22 and the end 25 of the conduit 21 being concealedby the tubular masking shell 28 which may be formed or decorated tosimulate a candle stick, so that upon positioning the lamp bulb 27therein a simulated can'dle effect is provided.

The shell 25 is formed of a single, threaded, preferably molded,insulating piece whose outward appearance is shown more in detail inFigures 3", 4, 5 and 6'. As shown in Figures 1, 2 and the shell 23 hasformed (pref erably molded) therein threads 31 formed in two separatediscontinuous sections separated by two diametrically opposed recesses33, 34' having straight parallel side's. These recesses 33, 34 areadapted to retain the contact members 24, 26, as will be described.Projections 35 extending toward one another from opposite sides of therecess 33 form a narrow groove at the outer end of recess 33. Similarprojections 36' form a similar groove at the outer end of recess 34.

As shown in Figures 1 and 8', contact member 24 is formed of a singlestrip of brass or similar conductive material having a wide portion 41and a narrower per: tion 42 bent at the line's- 43 to produce adoubled-over section 44 (as shown in Figure 1) and a contact-makingsection' 46 which resiliently cooperates with the center terminal of thebulb base as shown in dot and dash lines in Figure 1 to make electricalcontact therewith. The width of the wide portion 41 is slightly smallerthan the width of recess 33, but larger than the separation betweenprojections 35, so that contact 24- may be inserted in the groove at theend of recess 33, and retained there by projections 33. The narrowportion 42 of the contact member 24 is narrow enough as to pass freelybetween the projections 35 of the recess 33, which projections, however,prevent the wider portion 41 of contact member 24 from entering thecentral cavity of the shell 23.

The contact member 26 is formed of a single uniform width strip ofmaterial similar to contact member 24, and has a narrow ear 4'7 struckout from the center thereof. This car 47 passes freely between theprojections 36 of the recess 34 of shell 23 while the main portion isretained at the end of recess 34 by these projec tions and preventedfrom entering the main cavity of shell 23. As will be seen from Figure 1this ear 47 extends inwardly of the shell to a slight extent beyond theinnermost edge of the threads 31 so that upon screw ing the bulb 49 intothe socket it will make resilient eon= tact with the ear 47 at the bulbsouter threaded periph= ery to provide the necessary second electricalcontact for the bulb.

As seen in Figure 3, the base of the shell 23 has a pair of apertures 51through which the individual conductors 52 of the connecting line maypass, as indicated in Figure 1. In assembling the contact members 24 and26 the shell 23, the conductors 52, after having their ends' stripped ofinsulation, are fed through the apertures 51 to a position just abovethe upper edge of the shell. The contact members 24, 26 are then forceddown into their grooves in a manner to retain the stripped portion ofPatented Oct. 25, 1955 the conductors 52 between the contact members andthe insulating shell wall. The clearance therebetween is madesufficiently small so that the stripped ends of the conductors 52 arecrushed against the contact members 24, 26 to make good electricalcontact therewith. The upper corners 45 of the contact members 24, 26are bent slightly to form projections which dig into the wall of shell23, as shown in Figure 1, and prevent loosening or removal of thecontact members. Radially inward of each of the recesses 33, 34 is arespective projection 54 standing up from the inside of the base ofshell 23 and having a V-shaped profile as best seen in Figure 2. Eachconductor 52 passes over this V-shaped projection 53 to provide a strainrelief so that any pull of the conductor 52 will be opposed by the shell23 rather than resulting in any strain or separation between theconductor 52 and the contact member 24 or 26.

The base of the shell 23 is provided with a pair of further apertures 55preferably along the diameter transvers to the line joining theapertures 51. These apertures 55 are rectangular in shape and areadapted to receive the tips 61 of the hickey 22 shown in Figure 7. Thishickey 22 is essentially a U-shaped bracket having a pair of legs 62joined by a center section 63 which may have a threaded boss 64 formedat its center, as by extruding, pressing or threading. Each of the tips61 is joined by means of a narrow neck 67 to a respective shoulder 66projecting from each leg 62 of the hickey. Shoulder 66 and tip 61 are ofthe same width as the length of the slotted apertures 55 in the base ofthe shell 23, and the height of the shoulder 66 and neck 67 are slightlyless than the thickness of the bottom of shell 23. For assembly purposesthe tip 61 and neck 67 of each of the legs 62 is inserted in arespective opening 55 so that the shoulder 66 passes through the slot 55with the tip 61 extending above the floor of the base of the shell 23.Then simply by means of a pair of pliers or like instrument the tip 61is twisted from 45 to 90 with respect to the plane of its leg 62 therebyretaining the hickey fastened securely to the shell 23. It will beunderstood that the upper edges 68 of the hickey legs 62 bear againstthe flattened underside of the shell 23 as seen in Figure 4 and thetapered undersides 69 of tips 61 bear against the edges of the slots 55to hold the hickey securely fastened to the shell. The hickey and shellassembly may then be readily screwed on the threaded end of the conduit21. The masking shell 28 may then be readily slipped over the lampsocket shell 23 to be frictionally engaged therewith and to conceal thehickey 22 and the end of the conduit 21.

While one form of hickey has been illustrated in Figure 7 it will beunderstood that many other forms are possible and may be used wheredesired. Figures 10 and 11 illustrate two further forms of hickey. InFigure 10 the hickey is formed of a single strip of metal or similarmaterial with one of the tips 61a formed in the end thereof as in Figure7 and the second tip 61b formed on the end of an ear 71 struck out froma transversely extending section 72 of the hickey. Thus, only a singleleg 73 corresponding to leg 62 on Figure 7 need be provided, joined to afurther transverse portion 74 correspondinng to end 63 of Figure 7 andhaving the threaded boss 75 corresponding to boss 64 of Figure 7. Figure11 shows a further form of hickey whose shell securing end is the sameas in Figures 7 and 10, but instead of being adapted to be threaded upona conduit as in Figures 7 and 10, in this form of the invention the side73 is provided with a slot 74 which may be secured to any desiredsurface 81 by means of a clamping screw 82 or the like. The transverseportion 74 of the hickey shown in Figure 10 is here unnecessary and isomitted.

In many conventional forms of lamp socket the bulb 27 is screwed intothe socket shell until its lower tip 30 makes contact with the centersocket contact corresponding to 46 which is resilient to maintaincontact with the bulb tip 30. Under these circumstances the bulb 27 isnot rigidly held by the socket and during use any stray vibration orshock or the like tends to unscrew the bulb in the socket untileventually the pressure between the center socket connection and thebulb tip is of such light pressure as to cause arcing or to causedisconnection. According to the present invention, however, the socketshell 23 is provided with a plurality of upstanding projections 80illustrated in Figures 1, 2 and 3 as four in number and symmetricallylocated. These extend above the projections 54 and the conductors 52 aswell as above the twisted tips 61 of the hickey when assembled. In thisway, when the bulk is screwed into the socket a positive tightening isaccomplished by advancing the bulb 27 in the threads 31 until the edgeof the base of the bulb engages the projections 80. These projectionsare so located that the elastic limit of the lower contact 46 is notexceeded. In this way the bulb is retained in fixed positioncontinuously and constant pressure between the socket contact 46 and thebulb terminal 30 is maintained at all times.

Figures 12 through 19 show another form of lamp socket according to thepresent invention. Illustratively, this is shown as a socket forcandelabra sized lamp bulbs whereas Figures 1 to 11 have beenillustrated with respect to medium base lamp bulbs. However, it will beunderstood that the features of the present invention do not depend inany way upon the size of the socket or the lamp bulb base with which itcooperates, but may be used with any size base.

The lamp socket of Figures 12 to 19 is designed especially for use as aplug-in lamp such as used for a nightlight or guard-light or the like,and for this purpose the contact members for the lamp socket areextended integrally to form the prongs of a plug adapted to be directlyinserted into a plug receptacle such as a wall outlet or the like. Inthis way this device has but three parts readily assembled in the mannerto be described, these parts being shell 91 and the two contact-prongmembers 92, 93. As in the above figures, shell 91 is molded with a pairof threaded sections 94 separated by diametrically opposed recesses 96,97 having projections 98, 99 forming narrow grooves 101, 102 forreceiving the contact members. In this instance, however, the grooves101, 102 extend completely through the base 103 of the shell 91 as shownmost clearly in the bottom view of Figure 15.

The contact member 92 is shown in developed view in Figure 18 andcomprises a long section 104 and a short section 105 adapted to befolded back about line 106 to form the prong portion of element 92. Thesmaller portion 105 has a narrow section 107 adapted to be bent at line108 to form the central socket terminal 109 as shown in Figure 12.Struck out of the narrower section 107 is a small car or lug 111 adaptedto be bent about dotted line 112 to form a transverse projection asshown in Figure 12. It will be understood that the section 107 isnarrower than the separation between the projections 98 of Figure 14 sothat wider sections 104, 105 are retained within the groove 101, and thenarrower section 107 in the form of socket contact 109 and the lug 111may project into the central cavity of the shell 91. In assembly thebent contact member 92 is inserted through the top of the shell 91 andslid downwardly along groove 101 until lug 111 reaches the inside faceof the base 103 of shell 91. The corners 112 of the end of the longersection 104 are bent in as shown at 113 so that during the insertion ofthe member 92 these points 113 dig into the side wall of the shellmaterial and thereby prevent the element 92 from being moved upwardly ofthe shell. While this is a simple expedient which is found to be simpleand convenient in practice, it will be understood that where desiredother means of preventing removal of the member 92 may be utilized suchas suitable detents, shoulders or the like.

The contact member 93 is illustrated in Figure 19 and comprises a longerportion 116 and a shorter portion 117 adapted to be bent back injuxtaposition to portion 116 about a line 118 to form the prong portionof member 93. The short portion 117 has a small ear 119 extendingtherefrom adapted to be bent transversely of the prong portion about aline 121 to form a locating ear similar to 111, as seen in Figure 12.Struck outwardly from the center of the longer portion 116 is a strip122 having a slanting portion 123 and a parallel portion 124 as shown inFigure 12. This provides a lamp bulb base engaging contact similar to 47of Figure 1. Again, the corners 126 of the longer portion 116 are bentover to form points which engage the side wall of the shell 91 so thatafter placement of the member 93 in slot 102 it cannot be withdrawn fromthe socket shell.

To provide a positive tightening action characteristic of the presentinvention a pair of ledges 131 are formed on the inner surface of theshell wall extending above the inner surface of the shell base 103 andserving the same purpose as the projections 80 of Figure 3.

Accordingly, several forms of lamp socket have been described, accordingto the present invention, incorporating a positive tightening active forthe lamp bulb preventing loosening thereof during use and maintainingpositive contact with the contact members of the socket. As additionalfeatures of the present invention there has been shown an extremelysimple and inexpensive method of forming both the lamp socket shell andits hickey to provide simple and positive securing of one upon theother. As an additional feature, an extremely simple and inexpensivecombined lamp socket and plug arrangement has been shown having butthree parts which may be readily made and easily assembled.

While several embodiments of the present invention have been describedand illustrated in detail, it is to be understood that these embodimentsare exemplary only and are not to be considered in any way as limitingthe present invention, since many minor variations therefrom can bereadily conceived without departing from the spirit of the presentinvention, which is defined solely by the appended claims.

What is claimed is:

1. An electrical socket receptacle for electric light bulbs comprising ahollow insulated body open at one end to receive an electric light bulband having side walls and a base, with a pair of grooved recesses formedon the interior of said side Walls, electrical contact members slidablyseated in said grooved recesses and adapted to make electrical contactwith the base of said bulb, said contact members being provided withmeans at their lower ends to make electrical contact with the Wires ofan electrical conductor cord, one of said contact members having aresilient tongue bent over therefrom, said tongue extending across theinterior of said base and being spaced therefrom the interior walls ofsaid hollow body having threads formed therein and extending betweensaid grooved recesses and adapted to receive said bulb, said body wallalso having projections extending upwardly from said body base to makecontact with the bulb radially outwardly of its central contact and torestrict movement of said bulb base after contact with said tongue andprovide positive clamping means for said bulb base, whereby accidentalloosening of said bulb in said hollow body is inhibited.

2. An electrical socket receptacle for electric light bulbs comprising ahollow body of insulating material having a pair of oppositely disposedgrooved recesses formed on the interior thereof, said body also havingan end wall and being open at the opposite end thereto, a pair ofelectrical contact elements slidably seated in said grooved recesses andprovided with means at their lower ends adjacent said end wall to makeelectrical connection with the respective wires of an electricalconductor cord, one of said contact members having a resilient portionspaced from the interior face of said end wall and extending parallelthereto and at right angles to the side wall inwardly of said hollowmember to substantially the center thereof to make electrical contactwith the center base terminal of an electric light bulb and the otherelectrical contact member being provided with a projection extending butslightly inwardly of said hollow body member and generally axiallythereof and adapted to make electrical contact with the threaded shellof the base of an electric light bulb, the end Wall of said hollow bodyhaving a plurality of projections formed integrally thereon extendinginwardly and parallel to the axis of said hollow body and adapted toengage the bottom of said bulb base after said base engages saidresilient contact member portion and before engaging said end wall, saidhollow body being internally threaded to receive the threaded bulb basewhereby said wall projections and said threaded portion serve to rigidlyretain said bulb within said hollow body and in electrical contact withsaid contact members.

References Cited in the file of this patent UNITED STATES PATENTS726,832 Ritchel Apr. 28, 1903 1,727,148 White (B) Sept. 3, 19291,743,929 Nero Jan. 14, 1930 1,820,261 White Aug. 25, 1931 2,229,403Benander Jan. 21, 1941 2,309,311 Grohsgal Jan. 26, 1943 2,422,393 BryantJune 17, 1947 FOREIGN PATENTS 731,864 Germany Feb. 17, 1943

